Prior art containers for storing and dispensing mascara and similar cosmetic products have remained the same in design and function for several decades.
Devices for dispensing mascara compositions are known in the art. One such device comprises a tubular container, which serves as a reservoir for a mascara composition. The tubular container is open at one end. An applicator comprising a rod having bristles at one end and a cap portion at its other end is removably disposed in the container and in contact with the mascara composition in the container. Typically the rod and bristles are housed or submerged directly in the mascara composition. The cap portion serves as a closure for the open end of the tubular container. This is generally accomplished by providing the cap interior surface with threading adapted to engage threading on the exterior surface of the tubular container at its open end.
Generally, such prior art devices also include a wiper. The wiper is disposed within the tubular container. The wiper functions to remove excess mascara composition from the applicator bristles and rod when the applicator is removed from the tubular container for the purpose of applying the mascara composition to the eyelashes.
Such prior art devices have proven to be deficient in a number of respects. Typically they rely only on wiper to cap and wiper to rod contact for sealing the mascara composition contained therein from the atmosphere. As the mascara composition in the prior art container is used, the headspace (air space between the mascara composition and the side walls and top or bottom of the container) increases and the propensity for the mascara composition to dry out becomes more evident. This results in difficulty of use and shorter product life. Such devices generally permit dispensing of about 50 to 70% of the compositions contained therein. Moreover, the prior art devices repeatedly expose the bulk of the composition stored therein to the atmosphere during each use by the consumer. This serves to increase the risk of contamination by foreign substances such as particulate matter and microbes.
Moreover, such prior art devices are not suitable for storage and application of cosmetic compositions containing a significant concentration of one or more volatile agents, for example, the volatile agents contained in post-foaming mascara compositions, as described in U.S. patent application Ser. No. 10/331,069, PCT Application No. US03/40782, PCT Application No. PCT/US03/40790, and PCT Application No. PCT/US03/40789.
Heretofore, post-foaming mascara compositions containing volatiles, such as isopentane, required storage in closed containers. The present inventors' attempts to dispense such post-foaming compositions from the above described prior art devices met with failure. The prior art devices do not have the ability to contain compositions with volatile component(s) capable of generating a vapor pressure. Furthermore, prior art devices allow post-foaming or post-expanding compositions to pre-expand or foam resulting in a loss of efficacy. The compositions tended to dry out inside the devices. Each time the applicator was removed and reinserted in the prior art device air entered and caused drying of the mascara composition coating the inner surface of the reservoir housing the mascara composition. As the composition was used up, the headspace in the reservoir and the inner surface area where composition drying can occur increased. This led to further drying and loss of volatile composition components.
It is an object of the present invention to obviate the above described drawbacks of prior art mascara containers and dispensing devices.
It is a further object of the present invention to provide an improved container and dispensing mechanism wherein the cosmetic composition is housed separately from the applicator and the composition is only dosed onto the applicator, preferably, in a metered fashion.
It is another object of the present invention to provide a dispensing device in which the reservoir of unused product is kept separate from the used, contaminated or exposed composition.
It is yet another object of the present invention to provide a dispensing device in which headspace in the reservoir for the composition is substantially eliminated.
It is yet a further object of the present invention to provide a dispensing device that enables use of up to 95-99% of the composition contained therein.
It is still another object of the present invention to provide a dispensing device in which unused composition is kept from exposure to air. This is particularly important for air sensitive compositions.
An additional object of the present invention is to provide a dispensing device that enables delivery of a predetermined unit dose of composition contained therein.